1. Technical Field
The present invention relates to thermoelectric phase change cells and more particularly to a multilayered programmable device structure and method employing a thermoelectric material for storing a state in a phase change cell.
2. Description of the Related Art
There are many applications that involve probe tips to be used as movable electrical contacts. For example, in probe storage using phase change media, the probe is used to provide an electrical contact so that current can be applied to a predefined position of the storage media. In order to address several bits of stored information, the probe is able to move and make contact with individual bit positions.
Another example using probe tips includes probe-based patterning for micro and nanofabrication. In numerous methods of patterning, a current has to be applied locally to a point of a sample surface at which a physical or chemical modification is to be induced. This modification is later exploited to transform into a pattern or is the pattern itself.
Another example that involves probe tips includes metrology. For testing and characterizing of electronic devices, it is desirable to have local electrical probes available that can be used to locally address individual parts of circuits.
A generic problem for all of these applications, particularly when a nanoscale contact is used, is that the ability to pass electrical current from a probe to a substrate is subject to chemical and geometrical changes of the probe and/or the electrical contact to be addressed. The reasons for this are tribological, electrochemical or age related. It is therefore an unsolved problem to produce reliable formation of an electrical contact for various applications, especially for contact sizes in the nanometer regime.